Fuser member

ABSTRACT

The present teachings provide a fuser member, including a substrate and a release layer disposed on the substrate. The release layer includes a plurality of carbon nanotubes surrounded by a fluoroelastomeric shell layer and dispersed in a fluoroplastic.

BACKGROUND

1. Field of Use

This disclosure is generally directed to fuser members useful inelectrophotographic imaging apparatuses, including digital, image onimage, and the like.

2. Background

In a typical electrophotographic imaging apparatus, an image of anoriginal to be copied, or the electronic document image, is recorded inthe form of an electrostatic latent image upon a photosensitive memberand the latent image is subsequently rendered visible by the applicationof thermoplastic resin particles or composites thereof which arecommonly referred to as toner. The visible toner image is in a loosepowdered form and can be easily disturbed or destroyed. The toner imageis usually fixed or fused upon a substrate or support member which maybe a cut sheet or continuous media, such as plain paper.

The use of thermal energy for fixing toner images onto a support memberis well known. In order to fuse toner material onto a support surfacepermanently by heat, it is necessary to elevate the temperature of thetoner material to a point at which the constituents of the tonermaterial coalesce and become tacky. This heating causes the toner toflow to some extent into the fibers or pores of the support member.Thereafter, as the toner material cools, solidification of the tonermaterial causes the toner material to be firmly bonded to the support.

Several approaches to thermal fusing of toner images have been describedin the prior art. These methods include providing the application ofheat and pressure substantially concurrently by various means: a rollpair maintained in pressure contact; a belt member in pressure contactwith a roll; and the like. Heat may be applied by heating one or both ofthe rolls, plate members or belt members. The fusing of the tonerparticles takes place when the proper combination of heat, pressure andcontact time is provided. The balancing of these parameters to bringabout the fusing of the toner particles is well known in the art, andthey can be adjusted to suit particular machines or process conditions.

During operation of a fusing system in which heat is applied to causethermal fusing of the toner particles onto a support, both the tonerimage and the support are passed through a nip formed between the rollpair, or plate or belt members. The concurrent transfer of heat and theapplication of pressure in the nip affect the fusing of the toner imageonto the support. It is important in the fusing process that no offsetof the toner particles from the support to the fuser member take placeduring normal operations. Toner particles that offset onto the fusermember may subsequently transfer to other parts of the machine or ontothe support in subsequent copying cycles, thus increasing the backgroundor interfering with the material being copied there. The referred to“hot offset” occurs when the temperature of the toner is increased to apoint where the toner particles liquefy and a splitting of the moltentoner takes place during the fusing operation with a portion remainingon the fuser member. The hot offset temperature or degradation to thehot offset temperature is a measure of the release property of the fusermember, and accordingly it is desired to provide a fusing surface, whichhas low surface energy to provide the necessary release.

A fuser or image fixing member, which can be a rolls or a belt, may beprepared by applying one or more layers to a suitable substrate.Cylindrical fuser and fixer rolls, for example, may be prepared byapplying an elastomer or fluoroelastomer to an aluminum cylinder. Thecoated roll is heated to cure the elastomer. Such processing isdisclosed, for example, in U.S. Pat. Nos. 5,501,881; 5,512,409; and5,729,813; the disclosure of each of which is incorporated by referenceherein in their entirety.

Current fuser members may be composed of a resilient silicone layer witha fluoropolymer topcoat as the release layer. Fluoropolymers canwithstand high temperature) (>200° and pressure conditions and exhibitchemical stability and low surface energy, i.e. release properties.There are typically two types of fuser topcoat materials used for thecurrent fuser member—fluoroelastomers and fluoroplastics.Fluoroelastomers have good mechanical flexibility, provide shockabsorbing properties and typically require a release agent to preventoffset due to their higher surface energy. Fluoroplastics, such asTEFLON® also from E.I. DuPont de Nemours, Inc. have a lower surfaceenergy due to high fluorine content and are widely used for oil-lessfusing. However, fluoroplastics typically lack mechanical flexibility,which can cause, for example, denting, cracking, and abrasion.

SUMMARY

According to various embodiments, a fuser member, including a substrateand a release layer disposed on the substrate, is provided. The releaselayer includes a plurality of carbon nanotubes surrounded by afluoroelastomeric shell layer and dispersed in a fluoroplastic.

According to another embodiment, there is described a method of making afuser member. The method includes obtaining a substrate and coating acoating composition of carbon nanotubes having a fluoroelastomer shelllayer, a fluoroplastic, a curing agent and an organic solvent on thesubstrate. The coating composition is cured to form a release layer.

According to another embodiment, there is described an image renderingdevice which includes an image applying component for applying an imageto a copy substrate and a fusing apparatus, which receives the copysubstrate with the applied image from the image applying component andfixes the applied image more permanently to the copy substrate. Thefusing apparatus includes a fusing member and a pressure member whichdefine a nip therebetween for receiving the copy substrate therethrough.The fuser member includes a substrate and an outer layer disposed on thesubstrate release layer disposed on the substrate which includes aplurality of carbon nanotubes surrounded by a fluoroelastomer shelllayer dispersed in a fluoroplastic.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate several embodiments of thepresent teachings and together with the description, serve to explainthe principles of the present teachings.

FIG. 1 is a schematic illustration of an image apparatus.

FIG. 2 is a schematic of an embodiment of a fuser member.

FIG. 3 is a detailed diagram of a release layer.

It should be noted that some details of the FIGS. have been simplifiedand are drawn to facilitate understanding of the embodiments rather thanto maintain strict structural accuracy, detail, and scale.

DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to embodiments of the presentteachings, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts.

In the following description, reference is made to the accompanyingdrawings that form a part thereof, and in which is shown by way ofillustration specific exemplary embodiments in which the presentteachings may be practiced. These embodiments are described insufficient detail to enable those skilled in the art to practice thepresent teachings and it is to be understood that other embodiments maybe utilized and that changes may be made without departing from thescope of the present teachings. The following description is, therefore,merely exemplary.

Referring to FIG. 1, in a typical electrostatographic reproducingapparatus, a light image of an original to be copied is recorded in theform of an electrostatic latent image upon a photosensitive member andthe latent image is subsequently rendered visible by the application ofelectroscopic thermoplastic resin particles, which are commonly referredto as toner. Specifically, a photoreceptor 10 is charged on its surfaceby means of a charger 12, to which a voltage has been supplied from apower supply 11. The photoreceptor 10 is then imagewise exposed to lightfrom an optical system or an image input apparatus 13, such as a laserand light emitting diode, to form an electrostatic latent image thereon.Generally, the electrostatic latent image is developed by bringing adeveloper mixture from a developer station 14 into contact therewith.Development can be effected by use of a magnetic brush, powder cloud, orother known development process. A dry developer mixture usuallycomprises carrier granules having toner particles adheringtriboelectrically thereto. Toner particles are attracted from thecarrier granules to the latent image forming a toner powder imagethereon. Alternatively, a liquid developer material may be employed,which includes a liquid carrier having toner particles dispersedtherein. The liquid developer material is advanced into contact with theelectrostatic latent image and the toner particles are deposited thereonin image configuration.

After the toner particles have been deposited on the photoconductivesurface in image configuration, they are transferred to a copy sheet 16by a transfer means 15, which can be pressure transfer or electrostatictransfer. Alternatively, the developed image can be transferred to anintermediate transfer member, or bias transfer member, and subsequentlytransferred to a copy sheet. Examples of copy substrates include paper,transparency material such as polyester, polycarbonate, or the like,cloth, wood, or any other desired material upon which the finished imagewill be situated.

After the transfer of the developed image is completed, copy sheet 16advances to a fusing station 19, depicted in FIG. 1 as a fuser roll 20and a pressure roll 21 (although any other fusing components such asfuser belt in contact with a pressure roll, fuser roll in contact withpressure belt, and the like, are suitable for use with the presentapparatus), wherein the developed image is fused to copy sheet 16 bypassing copy sheet 16 between the fusing and pressure members, therebyforming a permanent image. Alternatively, transfer and fusing can beeffected by a transfix application.

Subsequent to transfer, photoreceptor 10 advances to a cleaning station17, wherein any toner left on photoreceptor 10 is cleaned therefrom byuse of a blade (as shown in FIG. 1), brush, or other cleaning apparatus.

FIG. 2 is an enlarged schematic view of an embodiment of a fuser member,demonstrating the various possible layers. As shown in FIG. 2, asubstrate 25 has an intermediate layer 22 thereon. Intermediate layer 22can be, for example, a silicone rubber. On intermediate layer 22 ispositioned a release layer 24, described in more detail below.

Shown in FIG. 3 is a release layer. The release layer includes acomposite material of carbon nanotubes (CNTs) 32 coated with afluoroelastomer shell layer 31 dispersed in a fluoroplastic 33. Such arelease layer provides a layer that is less brittle and less susceptibleto dents or cracks while providing a low surface energy for good tonerrelease. The CNTs 32 provide a hard core and the fluoroelastomerprovides a soft shell layer 31. The fluoroelastomer coated CNTs toughenthe fluoroplastic 33. The release layer can have a surface free energyof about 25 mN/m or less, wherein the surface free energy can becalculated, e.g., by using Lewis Acid-Base method from the results ofthe contact angle measurement using Fibro DAT1100 instrument.

Fluoroplastics suitable for use in the formulation described hereininclude fluoropolymers comprising a monomeric repeat unit that isselected from the group consisting of vinylidene fluoride,hexafluoropropylene, tetrafluoroethylene, perfluoroalkylvinylether, andmixtures thereof. Examples of fluoroplastics includepolytetrafluoroethylene (PTFE); perfluoroalkoxy polymer resin (PFA);copolymer of tetrafluoroethylene (TFE) and hexafluoropropylene (HFP);copolymers of hexafluoropropylene (HFP) and vinylidene fluoride (VDF orVF2); terpolymers of tetrafluoroethylene (TFE), vinylidene fluoride(VDF), and hexafluoropropylene (HFP); and tetrapolymers oftetrafluoroethylene (TFE), vinylidene fluoride (VF2), andhexafluoropropylene (HFP), and mixtures thereof. The fluoroplasticprovides chemical and thermal stability and has a low surface energy.The fluoroplastic has a melting temperature of from about 100° C. toabout 350° C. or from about 120° C. to about 330° C.

As used herein and unless otherwise specified, the term “carbonnanotube” or CNT refers to an elongated carbon material that has atleast one minor dimension (for example, width or diameter of up to 100nanometers). In various embodiments, the CNT can have an averagediameter ranging from about 1 nm to about 100 nm, or in some cases, fromabout 5 nm to about 50 nm, or from about 10 nm to about 30 nm. Thecarbon nanotubes have an aspect ratio of at least 10, or from about 10to about 1000, or from about 10 to about 5000. The aspect ratio isdefined as the length to diameter ratio.

In various embodiments, the carbon nanotubes can include, but are notlimited to, carbon nanoshafts, carbon nanopillars, carbon nanowires,carbon nanorods, and carbon nanoneedles and their various functionalizedand derivatized fibril forms, which include carbon nanofibers withexemplary forms of thread, yarn, fabrics, etc. In one embodiment, theCNTs can be considered as one atom thick layers of graphite, calledgraphene sheets, rolled up into nanometer-sized cylinders, tubes, orother shapes.

In various embodiments, the carbon nanotubes or CNTs can includemodified carbon nanotubes from all possible carbon nanotubes describedabove and their combinations. The modification of the carbon nanotubescan include a physical and/or a chemical modification.

In various embodiments, the carbon nanotubes or CNTs can include singlewall carbon nanotubes (SWCNTs), multi-wall carbon nanotubes (MWCNTs),and their various functionalized and derivatized fibril forms such ascarbon nanofibers.

The CNTs can be formed of conductive or semi-conductive materials. Insome embodiments, the CNTs can be obtained in low and/or high puritydried paper forms or can be purchased in various solutions. In otherembodiments, the CNTs can be available in the as-processed unpurifiedcondition, where a purification process can be subsequently carried out.

One of ordinary skill in the art would understand that the CNT coreelement of the core-fluoroelastomer shell layer can have various othercross sectional shapes, regular or irregular, such as, for example, arectangular, a polygonal, or an oval shape. Accordingly, the CNT 32 canhave, for example, cylindrical 3-dimensional shapes.

The carbon nanotubes coated with a fluoroelastomer shell are present inan amount of from about 0.1 percent to about 20 percent based on aweight of the release layer. A further example is from about 0.5 percentto about 15 percent, or from about 1 percent to about 10 percent weightpercent based weight of the release layer.

The fluoroelastomer shell layer includes a polymer selected from thegroup consisting of fluoroelastomer, a perfluoroelastomer,perfluoropolyether, a silicone, a fluorosilicone, and mixtures thereof.

Examples of three known fluoroelastomers are (1) a class of copolymersof two of vinylidenefluoride, hexafluoropropylene, andtetrafluoroethylene, such as those known commercially as VITON A®; (2) aclass of terpolymers of vinylidenefluoride, hexafluoropropylene, andtetrafluoroethylene known commercially as VITON B®; and (3) a class oftetrapolymers of vinylidenefluoride, hexafluoropropylene,tetrafluoroethylene, and cure site monomer known commercially as VITONGH® or VITON GF®.

The fluoroelastomers VITON GH® and VITON GF® have relatively low amountsof vinylidenefluoride. The VITON GF® and VITON GH® have about 35 weightpercent of vinylidenefluoride, about 34 weight percent ofhexafluoropropylene, and about 29 weight percent of tetrafluoroethylene,with about 2 weight percent cure site monomer.

Commercially available fluoroelastomers used for the shell layer 31 inFIG. 3 can include, such as, for example, VITON® A (copolymers ofhexafluoropropylene (HFP) and vinylidene fluoride (VDF or VF2)), VITON®B, (terpolymers of tetrafluoroethylene (TFE), vinylidene fluoride (VDF)and hexafluoropropylene (HFP)), and VITON® GF, (tetrapolymers of TFE,VF2, HFP), as well as VITON® E, VITON® E 60C, VITON® E430, VITON® 910,VITON® GH and VITON® GF. The VITON® designations are trademarks of E.I.DuPont de Nemours, Inc. (Wilmington, Del.).

In a specific embodiment, the fluoroelastomers for the shell layer 31can include VITON-GF® (E.I. du Pont de Nemours, Inc.), including TFE,HFP, and VF2, and a cure site. Exemplary curing agent for this elastomercan include VITON® Curative No. 50 (VC-50) available from E.I. du Pontde Nemours, Inc. Curative VC-50 can contain Bisphenol-AF as across-linker and diphenylbenzylphosphonium chloride as an accelerator.

In various embodiments, the fluoroelastomer shell layer 31 can beattached to the CNT 31 by physical or chemical bonds through, forexample, a functional group of the elastomers that is capable of bondingwith the carbon nanotubes. In an exemplary embodiment, thefluorelastomeric materials used for the shell layer 31 can have achemically functional group capable of reacting with CNT or modified CNTby a covalent bond so as to form a shell layer 31 surrounding the CNT32. The functional group can include, but is not limited to, hydroxyl,carboxylic acid, aziridine, azomethine ylide, aryl diazonium cation,oxazolidinone, and mixtures thereof.

In various embodiments, the shell layer 31 can have a shell thicknessT_(s) on the outer surface of the CNT hard core 32. In variousembodiments, the shell thickness T_(s) can be at least about 1 nm. Inembodiments, the shell thickness T_(s) can be in a range from about 1 nmto about 5 nm, or in some cases, from about 1 nm to about 1000 nm.

In various embodiments, the fluoroelastomers used for the shell layer 31can be present in an amount of from about 1% to 50% by weight of thefluoroplastic 33. In an additional example, the fluoroelastomers usedfor the shell layer 31 can be present in an amount of from about 2% toabout 20% by weight of the fluoroplastic 33, or in some cases from about2% to about 10% by weight of the fluoroplastic 33. Other possible amountof fluoroelastomers can also be included in the present teachings.

In various embodiments, other filler materials, for example inorganicparticles, can be used for the coating composition and the subsequentlyformed release layer. In various embodiments, exemplary inorganicparticles can include metal oxides, non-metal oxides, and metals.Specifically, the metal oxides can include, for example, silicon oxide,aluminum oxide, chromium oxide, zirconium oxide, zinc oxide, tin oxide,iron oxide, magnesium oxide, manganese oxide, nickel oxide, copperoxide, antimony pentoxide, and indium tin oxide. The non-metal oxidescan include, for example, boron nitride and silicon carbides (SiC). Themetals can include, for example, nickel, copper, silver, gold, zinc, andiron. In various embodiments, other additives known to one of ordinaryskill in the art can also be included to form the disclosed compositematerials.

The thickness of the release layer of the fuser member is from about 10to about 250 micrometers, or from about 15 to about 100 micrometers, orfrom about 20 to about 50 micrometers.

The surface resitivity of the release comprises a surface resistivity is10⁸ Ω/sq or less.

Various embodiments can also include a method for making the releaselayer in accordance with the present teachings. It will be appreciatedthat the present invention is not limited by the illustrated ordering ofsuch acts or events. For example, some acts may occur in differentorders and/or concurrently with other acts or events apart from thoseillustrated and/or described herein, in accordance with the presentteachings. In addition, not all illustrated steps may be required toimplement a methodology in accordance with the present teachings.

The coating composition can also be prepared to include, for example, aneffective solvent, in order to disperse the fluoroelastomer coatedcarbon nanotubes, fluoroplastic, and optionally, inorganic fillerparticles that are known to one of ordinary skill in the art.

The effective solvents can include water and/or organic solventsincluding, but not limited to, methyl isobutyl ketone (MIBK), acetone,methyl ethyl ketone (MEK), and mixtures thereof. Other solvents that canform suitable dispersions can be within the scope of the embodimentsherein.

In various embodiments, the coating composition can be coated using, forexample, coating techniques, extrusion techniques and/or moldingtechniques. As used herein, the term “coating technique” refers to atechnique or a process for applying, forming, or depositing a dispersionto a material or a surface. Therefore, the term “coating” or “coatingtechnique” is not particularly limited in the present teachings, and dipcoating, painting, brush coating, roller coating, pad application, spraycoating, spin coating, casting, or flow coating can be employed.

The coating composition for the release layer is prepared byshear-mixing fluoroelastomer-coated CNT with a type of fluoroplastic,for example, THVP210 from Dyneon. The resulting coating dispersion isprepared by mixing the coating composition with a curing agent (e.g. VC50/metal oxide or AO700) in an organic solvent (e.g. MIBK). The fusertopcoat is fabricated by coating the dispersion on the fuser substrateand thermally curing the coating at elevated temperatures, for example,from about 150° C. stepwise increased to about 177° C., about 204° C.and to about 230° C. Compared with a fluoroplastic control having nofluoroelastomer coated carbon nanotubes, the fluoroelastomer coated CNTsdispersed in fluoroplastic composite show a significant increase inmechanical toughness while the surface free energy is not altered.

The substrate 25 in FIG. 2 can be in a form of, for example, a belt,plate, and/or cylindrical drum for the disclosed fuser member. Thesubstrate of the fusing member is not limited, as long as it can providehigh strength and physical properties that do not degrade at a fusingtemperature. Specifically, the substrate can be made from a metal, suchas aluminum or stainless steel or a plastic of a heat-resistant resin.Examples of the heat-resistant resin include with high strength includea polyimide, an aromatic polyimide, polyether imide, polyphthalamide,polyester, and a liquid crystal material such as a thermotropic liquidcrystal polymer and the like. The thickness of the substrate fallswithin a range where rigidity and flexibility enabling the fusing beltto be repeatedly turned can be compatibly established, for instance,ranging from about 10 to about 200 micrometers or from about 30 to about100 micrometers.

The intermediate layer 22 can include, for example, a rubber layer. Theresilient layer provides elasticity and can include a silicone rubber asa main component and be mixed with inorganic particles, for example SiCor Al₂O₃, as required.

Examples of suitable intermediate layers include silicone rubbers suchas room temperature vulcanization (RTV) silicone rubbers, hightemperature vulcanization (HTV) silicone rubbers, and low temperaturevulcanization (LTV) silicone rubbers. These rubbers are known andreadily available commercially, such as SILASTIC® 735 black RTV andSILASTIC® 732 RTV, both from Dow Corning; 106 RTV Silicone Rubber and 90RTV Silicone Rubber, both from General Electric; and JCR6115CLEAR HTVand SE4705U HTV silicone rubbers from Dow Corning Toray Silicones. Othersuitable silicone materials include the siloxanes (such aspolydimethylsiloxanes); fluorosilicones such as Silicone Rubber 552,available from Sampson Coatings, Richmond, Va.; liquid silicone rubberssuch as vinyl crosslinked heat curable rubbers or silanol roomtemperature crosslinked materials; and the like. Another specificexample is Dow Corning Sylgard 182. Commercially available LSR rubbersinclude Dow Corning Q3-6395, Q3-6396, SILASTIC® 590 LSR, SILASTIC® 591LSR, SILASTIC® 595 LSR, SILASTIC® 596 LSR, and SILASTIC® 598 LSR fromDow Corning.

The thickness of the intermediate layer is from about 0.5 to about 20mm, or from about 1 to about 7 mm.

Example 1 Preparation of a THVP/2% CNT/Viton Composite Coating

About 12 parts of multi-walled carbon nanotubes and 88 parts of Viton GF(available from E.I. du Pont de Nemours, Inc.) were placed in a HaakeRheomix mixer (from Thermo Scientific), and compounded at a rotor speedof 20 rpm for 30 minutes to form nanotube masterbatch containing 12weight percent of carbon nanotubes dispersed and coated in Viton GF. 13parts of the resulting carbon nanotube Viton GF masterbatch were thencompounded with 67 grams of THVP221 (a fluoroplastic available fromDyneon) at about 80° C. in a Haake Rheomix at a rotor speed of 20 rpmfor 30 minutes to form a composition containing about 2 weight percentof carbon nanotubes covering a Viton GF elastomer shell.

The THVP/CNT/Viton composition (4.18 Parts) was mixed with the metaloxides (0.787 part of magnesium oxide and 0.393 part of calciumhydroxide), and 1.68 parts of the bisphenol VC-50 curing agent (Viton®Curative No. 50 available from E.I. du Pont de Nemours, Inc.) in methylisobutyl ketone (28.4 parts). The resulting coating composition was thencast in a mold. The resulting film after solvent evaporation was curedat ramp temperatures of about 149° C. for 2 hours, about 177° C. for 2hours, about 204° C. for 2 hours and at about 232° C. for 6 hours. Thecured film was subjected to mechanical testing. The mechanical testingwas performed using ASTM D412 Tensile Properties of Elastomers. Theresults are summarized in table 1.

Example 2 Preparation of a THVP/3% CNT/Viton Composite Coating

A polymer composite coating containing about 3 weight percent of carbonnanotubes covering a Viton elastomer shell was prepared following theprocedure described in Example 1, except that 20 grams of CNTmasterbatch and 60 grams of THVP221 were used to make the THVP/3%CNT/Viton composite materials. The THVP/3% CNT/Viton composition (4.225Parts) was mixed with the metal oxides (0.787 part of magnesium oxideand 0.393 part of calcium hydroxide), and 1.9 parts of the bisphenolVC-50 curing agent (Viton® Curative No. 50 available from E.I. du Pontde Nemours, Inc.) in methyl isobutyl ketone (28.5 parts). The resultingcomposition was then cast in a mold. The resulting film after solventevaporation was cured at ramp temperatures of from about 149° C. for 2hours, about 177° C. for 2 hours, about 204° C. for 2 hours and at about232° C. for 6 hours. The results are summarized in table 1.

Comparative Example 1 Preparation of a THVP Coating

The THVP coating was prepared by mixing the THVP221 (4.10 parts), metaloxides (0.787 part of magnesium oxide and 0.393 part of calciumhydroxide), and 1.68 parts of the bisphenol VC-50 curing agent (Viton®Curative No. 50 available from E.I. du Pont de Nemours, Inc.) in methylisobutyl ketone (27.5 parts). The resulting coating composition was thencast in a mold. The resulting film after solvent evaporation was curedat ramp temperatures of from about 149° C. for 2 hours, about 177° C.for 2 hours, about 204° C. for 2 hours and at about 232° C. for 6 hours.The results are summarized in Table 1.

Comparative Example 2 Preparation of a THVP/Viton Composite Coating

THVP/Viton composite coating was prepared following the proceduredescribed in Example 1, except that 68 grams of THVP221 and 12 grams ofViton GF pellets GF (available from E.I. du Pont de Nemours, Inc.) wereused to produce the coating composition. The coating film was castfollowing the procedure described in comparative Example 1.

TABLE 1 Film Tensile Tensile Modulus Thickness stress strain (Young's)Examples (mil) (Psi) (%) (Psi) Toughness Example-1 13.7 955.6 142.11740.1 806.3 Example-2 17.6 1223.8 158.5 4397.5 1283.0 Comparative 14.8327.7 136.9 928.7 332.7 Example -1 Comparative 13.2 499.2 163.2 1044.6546.5 Example-2

Fluoroplastic materials are known to provide required releasingproperties for fusing. However, they are semi-crystalline materials, andare prone to ductile failure due to their inherent brittleness. Onestrategy to improve the mechanical performance of semi-crystallinepolymers is achieved by adding rubber fillers. Although fracturetoughness can be significantly improved, the rubber-toughened polymerstypically result in dramatic drop in modulus. As shown in Table 1 theuse of fluoroelastomer coated CNTs in a fluoroplastic coating providessuperior tensile strain, toughness, tensile stress and Young's Modulusover a fluoroplastic coating without fluoroelastomer coated CNTs. Thus,a superior release layer for fuser members is provided.

Other embodiments of the present teachings will be apparent to thoseskilled in the art from consideration of the specification and practiceof the present teachings disclosed herein. It is intended that thespecification and examples be considered as exemplary only, with thetrue scope and spirit of the present teachings being indicated by thefollowing claims.

1. A fuser member, comprising a substrate, and a release layer disposedon the substrate comprising a plurality of core-shell particlescomprising carbon nanotubes surrounded by a fluoroelastomer shell layerwherein the plurality of core-shell particles are dispersed in afluoroplastic.
 2. The fuser member of claim 1, wherein the fluoroplasticcomprises one or more monomeric repeat units selected from the groupconsisting of tetrafluoroethylene, vinylidene fluoride,hexafluoropropylene, chlorotrifluoroethylene, perfluoro(methyl vinylether), perfluoro(ethyl vinyl ether) and perfluoro(propyl vinyl ether).3. The fuser member of claim 1, wherein the fluoroplastic is selectedfrom the group consisting of polytetrafluoroethylene (PTFE);perfluoroalkoxy polymer resin (PFA); copolymer of tetrafluoroethylene(TFE) and hexafluoropropylene (HFP); copolymers of hexafluoropropylene(HFP) and vinylidene fluoride (VDF or VF2); terpolymers oftetrafluoroethylene (TFE), vinylidene fluoride (VDF), andhexafluoropropylene (HFP); and tetrapolymers of tetrafluoroethylene(TFE), vinylidene fluoride (VF2), and hexafluoropropylene (HFP).
 4. Thefuser member of claim 1, wherein the fluoroelastomer shell layer has athickness of from about 1 nanometer to about 1000 nanometers.
 5. Thefuser member of claim 1, wherein the fluoroelastomer shell layercomprises a polymer selected from the group consisting offluoroelastomer, a perfluoroelastomer, perfluoropolyether, a siliconeand a fluorosilicone.
 6. The fuser member of claim 1, wherein thefluoroelastomer shell layer further comprises a cross-linker.
 7. Thefuser member of claim 1, wherein fluoroelastomer shell layer furthercomprises a functional group capable of bonding with a carbon nanotube.8. The fuser member of claim 7, wherein the functional group capable ofbonding with the carbon nanotube is selected from the group consistingof a hydroxyl, a carboxylic acid, an aziridine, an azomethine ylide, anazide, an aryl diazonium cation, an oxazolidinone, and mixtures thereof.9. The fuser member of claim 1, wherein the carbon nanotubes comprise anaspect ratio ranging from about 10 to about
 5000. 10. The fuser memberof claim 1, wherein of the carbon nanotubes comprise a single wallcarbon nanotube (SWCNT) or a multi-wall carbon nanotube (MWCNT).
 11. Thefuser member of claim 1, wherein the plurality of core-shell particlesis present in an amount of about 0.5 percent to about 20 percent basedon a weight of the release layer.
 12. The fuser member of claim 1,wherein the release layer further comprises filler materials selectedfrom the group consisting of metal oxides, non-metal oxides and metals.13. The fuser member of claim 1, wherein the release layer comprises athickness of from about 10 to about 250 micrometers.
 14. The fusermember of claim 1, wherein the release layer has a surface energy of 25mN/m or less.
 15. The fuser member of claim 1, wherein the releasecomprises a surface resistivity of 10⁸ Ω/sq or less.
 16. The fusermember of claim 1, further comprising an intermediate layer disposedbetween the substrate and the release layer.
 17. The fuser member ofclaim 16, wherein the intermediate layer comprises a silicone material.18. A method of making a fuser member for fixing a developed image to acopy substrate, comprising: obtaining a substrate; coating a coatingcomposition of a plurality of carbon nanotubes with a fluoroelastomershell layer, a fluoroplastic, a curing agent and an organic solvent onthe substrate; and curing coating composition to form a release layer.19. The method of claim 18, wherein the organic solvent is selected fromthe group consisting of methyl isobutyl ketone (MIBK), acetone andmethyl ethyl ketone (MEK).
 20. An image forming apparatus for formingimages on a recording medium comprising a charge-retentive surface toreceive an electrostatic latent image thereon; a development componentto apply toner to the charge-retentive surface to develop anelectrostatic latent image to form a developed image on thecharge-retentive surface; a transfer component to transfer the developedimage from the charge retentive surface to a copy substrate; and a fusermember for fusing toner images to a surface of the copy substrate,wherein said fuser member comprises a substrate, and thereover, an outerlayer comprising a plurality of core-shell articles comprising carbonnanotubes surrounded by a fluoroelastomer shell layer wherein theplurality of core-shell particles are dispersed in a fluoroplastic,wherein the outer layer has surface free energy of 25 mN/m or less.